Various medical procedures require the administration of liquids, such as parenteral fluids, blood and enteral products, to a patient. These fluids are typically administered to the patient under gravity flow. For example, an IV (intraveneous) administration set comprising a source of the fluid, a flexible conduit and a valve may be used to administer these fluids.
One commonly used valve is a roller clamp. A roller clamp includes a body, a rotary or control member mounted on the body for rotation and translation relative to the body and a ramp on the body. The flexible conduit is received between the rotary member and the ramp. Accordingly, by rotating the rotary member, the rotary member translates along the ramp to selectively restrict the conduit to control the flow of fluid through the conduit to the patient.
The roller clamp is manually controlled. However, it is known to control a particular valve of unique construction with a stepper motor, and one such apparatus is disclosed in Cannon U.S. Pat. No. 4,300,552. This patented apparatus cannot be used to drive the roller clamp described above. Other automatic control apparati that also cannot be used to drive a roller clamp are shown in Lamadrid U.S. Pat. No. 4,397,642 and Sadlier et al U.S. Pat. No. 4,105,028.